title: Stratospheric water vapor feedback.
abstract: We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry-climate model to be +0.3 W/(m(2)⋅K), which would be a significant contributor to the overall climate sensitivity. One-third of this feedback comes from increases in water vapor entering the stratosphere through the tropical tropopause layer, with the rest coming from increases in water vapor entering through the extratropical tropopause.
authors.affiliation: Department of Atmospheric Sciences, Texas A&M University, College Station, TX 77843.
authors.forename: A E
authors.initials: AE
authors.lastname: Dessler
authors.forename: M R
authors.initials: MR
authors.lastname: Schoeberl
authors.forename: T
authors.initials: T
authors.lastname: Wang
authors.forename: S M
authors.initials: SM
authors.lastname: Davis
authors.forename: K H
authors.initials: KH
authors.lastname: Rosenlof
mesh_terms: D001272:Atmosphere / Q000737:chemistry*; D057231:Climate Change; D055907:Climatic Processes; D005246:Feedback; D017752:Greenhouse Effect; D008962:Models, Theoretical; D013227:Steam / Q000032:analysis*
chemical_list: D013227:Steam
keywords: climate change; lowermost stratosphere; overworld